1. Field of the Invention
The present invention relates to a color facsimile apparatus for color-printing color image data received through facsimile communication onto a predetermined recording sheet.
2. Description of Related Art
It is known that, in transmission of image data via facsimile communication, the data of the sending capability of a sending facsimile apparatus and of the receiving capability of a receiving facsimile apparatus are exchanged in the mutual transmission of protocol signals to be performed before transmission of the image data. The transmission of the image data is then performed according to the contents of the communication capability matched between both the sending and receiving apparatuses.
For this reason, a conventional color facsimile apparatus is constituted such that, when that color facsimile apparatus is on the receiving side, the receiving facsimile apparatus always sends a protocol signal to notify the sending facsimile apparatus that the receiving facsimile apparatus provides the color receiving capability.
Further, when color image data are received via facsimile communication, the conventional facsimile apparatus is constituted to handle the received image data always as the color image data. Namely, in the conventional color facsimile apparatus, the received color image data are stored in a memory as they are. And, when transferring the color image data to the printing section for printing on a recording sheet, the color image data are transferred to the printing section as they are.
However, the conventional color facsimile apparatus is constituted such that the receiving apparatus sends data to the sending apparatus notifying that the receiving apparatus has the color receiving capability, so that, if the sending apparatus is a color facsimile apparatus and the image data to be sent by the same are color image data, the receiving apparatus always receives the color image data. Hence, conventionally, the following problems are sometimes encountered.
Usually, color image data are constituted of at least three kinds of data representing tones of red, green, and blue (R, G, B). Compared with monochrome image data represented by digital signals of "0" and "1," the volume of the color image data is far greater than that of the monochrome image data per document for example. Consequently, in a so-called intercepting reception held for printing (reception by a memory) in which image data received by facsimile communication are sequentially stored in a memory before being printed, color image data being received often overflows the memory to cause a communication error, which seldom happens in the case of monochrome image data.
In addition, some color facsimile apparatuses incorporate a color printer that prints received color image data on a recording sheet in color ink. Such color facsimile apparatuses cannot print in color if the color ink is exhausted. In the conventional color facsimile apparatus, however, color image data are received and processed as color image data regardless of the situation in which color printing is difficult as described above. Consequently, conventionally, the received color image data cannot be outputted on a recording sheet properly, thereby making it impossible to confirm the contents of the received image data.
Further, in the facsimile apparatus of the above-mentioned type, even if color printing can be performed properly or there is a memory space enough for storing image data, users sometimes desire to process color image data as monochrome image data in order to save color ink, allocate a memory space, or shorten communication time. Conventionally, however, as described above, if the sending facsimile apparatus is a color facsimile apparatus that sends color image data, the receiving facsimile apparatus always receives the color image data and processes the received image data always as color image data, failing to meet the above-mentioned user requirements.